But the show didn't just bring the actor a large fanbase. It was even responsible for introducing him to his future wife - actress Rose Leslie, who played Ygritte, his romantic interest in the series.
Together for 13 years, the couple tied the knot in 2018 and now have a three-year-old son and 15-monthold daughter, whose names they have kept private.
And although Kit has since starred in Netflix series Criminal: UK and Extrapolations on Apple TV+, the HBO drama Industry, set in the high-octane, ruthless and sexy world of finance, marks his return to the small screen after five years.
The son of businessman and baronet Sir David Harington, Kit, 37, plays Sir Henry Muck in the eight-part series - a part not too far removed from his own pedigree.
"I've known a lot of people like Henry," says the actor, a distant descendant of King James I and Lord Harington of Exton.
"I think what I found fascinating about him was that he can't see his own privilege, amazingly. He's within this net of privilege that he can't see out of and he can't see how he's held.
This story is from the October 21, 2024 edition of HELLO! UK.
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This story is from the October 21, 2024 edition of HELLO! UK.
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